Operating mechanism



March 22, 1938. c. THUMIM OPERATING MECHANISM Filed Nov. 19, 1956 2 Sheets-Sheet l Inventor I Car-l Thurnirn, b9 J MZZ-JWIL all Hi ttor-neg.

March22, 1938. c. THUMIM ,1

OPERATING MECHANISM Filed Nov. 19, 1956 2 Sheets-Sheet 2 Inventor Car! Thumi'm,

low aw His Attor neg.

, Patented'Mar. 22, 1938 OPERATING MECHANISM Carl Thumim, Lansdowne, Pa., assignor to General Electric Company, a corporation of New York Application November 19, 1936,- Serial No. 111,709

6 Claims.

My invention relates to operating mechanisms, more particularly to those of the solenoid actuated type, and has'for its principal object the provision of an improved operating mechanism of the aforesaid type which is simple, compact and rugged in construction, emcient, positive and trip-free in operation and which is adapted to apply the operating force directlyto a member to be actuated reciprocally movable in a direction generally transverse to the direction of.

movement of the solenoid armature or plunger.

My invention will be more fully set forth in the following description referring to the accompanying drawings, and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

Referring to the drawing Fig. 1 is an elevational view partly in section of a solenoid operated mechanism in the operated or closed position embodying the present invention; Fig. 2 is a similar view showing the mechanism in an intermediate position during the releasing or tripping operation, and Fig. 3 is a similar view showing the mechanism in the open and reset positio l The operating mechanism ,herein described, while generally applicable to reciprocally movable devices, has particular application to electric cir 3 c'uit breakers wherein a switch member is movable between open and closed circuit positions. In such applications the switch member is generally moved to the closed circuit position against an opening biasing force, such as a compression spring, for example, so that the opening stroke is automatically accomplished simply by release of the switch member. In' circuit breaker mechanisms it is also desirable that the device be tripfree in operation, that is, free to trip and release the switch member during any part of the actuating or closing stroke.

Referring more particularly to Fig. 1 there is shown an actuating solenoid generally indicated at l including a reciprocally movable plunger 2 which is directly connected through a flexible tension member 3, such as a roller chain linkage for example, to a reciprocally movable switch 4 constituting the means to be actuated; In the present instance the direction of movement of the switch member is substantially at right angles to the direction of movement of the solenoid plunger, so that the chain linkage in applying the actuating force is guided so'as'to define an angle of approximately 90 degrees.

For the purpose of guiding and restraining the I mounted at l3 and coacting with a pin l 9 carried chain linkage in its operative position, a bell crank 5 pivotally mounted at 6 is provided at one end as at I with a roller 8. The bell crank is also provided with a loop-shaped guard member 9 which serves to keep the chain linkage within 5 the groove defined by the roller. The bell crank 5 is also provided at its opposite end as at In with a roller ll coacting with tripping or restraining means comprising a latch 12 pivotally mounted at l3. The latch is provided with an 10 offset arm M for coacting with the conventional tripping solenoid l5 and is spring biased for resetting at it in a counterclockwise direction v against the stop member ll.

It will be apparent that actuation of the trip- 15 ping solenoid to elevate the tripping plunger l5 causes clockwise rotation of the extension l4 and movement of the latch 02 beneath the roller ll. Manual tripping of the latch is suitably provided by means of a lever l8 independently pivotally by the extension arm 11 A manually operable link 28 is connected to the lever it for rotating the latch clockwise in the manner above described.

In the position shown by Fig. l the switch member is in the operated or closed circuit position and is held in'such position against the bias of a compression spring 20. The chain linkage 3 is held under tension by the solenoid plunger 30 while the solenoid is energized. When the solenoid is deenergized a prop member 22 pivotally mounted at 23 is biased as at 24 to block and hold the solenoid plunger in its lower or operated position. The prop 22 is adapted to abut at its lower end a guide pin 25 extending transversely of the plunger within a recess in the central part thereof and operable within lateral guide plates 25'.

The bell crank ii, the pivot 6 of which is offset with respect to the bisector of the angle defined by the chain linkage so that the chain tension tends to rotate the bell crank clockwise, is re-' strainedwith respect to clockwise rotation by the latch l2 as previously described. In this position the solenoid can be deenergized and the switch 5 member l held indefinitely in the closed circuit position.

The releasing or circuit opening operation is initiated by releasing or tripping of the bell crank by the latch it, either by the tripping solehold or manual operation, so that the spring 2l tensioning the chain linkage 3 causes clockwise rotation of the bell crank to the position shown by Fig. 2. A comparatively sensitive tripping device can be used if desired since the required tripping force is directly related to the crank lever arm indicated at a through which the resultant reacting force at the chain linkage tends to produce clockwise rotation of the crank. Where the lever arm a is quite small, the latch releasing force required is obviously small.

During the releasing movement of the bell crank a portion thereof at 5 serves as a cam member for engaging an extension 26 secured to the prop 22. After predetermined rotation of the bell crank the member 26 is cammed so as to move the prop 22 away from the solenoid pin 25. Accordingly the plunger 2; which is normally biased, in addition to the bias of spring 2|, by a spring 21 towards its upper or reset position, is now free to assume such position.

It will be apparent that release of the bell crank 5 causes sumcient slack in the chain linkage to permit immediate opening movement of the switch member. In addition, the release of the solenoid plunger in response to release of the bell crank causes immediate resetting of the solenoid so that another reclosing operation is dependent only upon resetting of the bell crank and latch. To this end the bell crank is provided with a resetting spring 28 which is tensioned during the opening operation and which functions immediately to reset the bell crank as illustrated by Figs. 2 and 3 as soon as there is suflicient slack in the chain linkage. I

In resetting the'roller II, the bell crank rides over the edge of the latch l2, thereby effecting resetting of the tripping means. The mechanism illustrated by Fig. 3 is therefore in the completely reset position and can be closed by energization of the solenoid causing downward movement of the plunger 2 to the position illustrated by Fig. 1.

During the closing operation the bell crank 5 is held in the position shown and the chain link age is guided by the roller 8 so that the actuating force is applied through an angle of 90 degrees without appreciable friction losses. When the plunger 2 reaches the lower position shown by- Fig. l the prop 22 is snapped by its spring 24 over the pin 25 so as to block return movement of the plunger except in accordance with a duly initiated opening operation. A

It will be noted that the mechanism is tripfree in all positions thereof during the actuating or closing stroke. That is, actuation of the tripping mechanism is effective at any time to produce suflicient slack in the chain linkage to permit reverse or opening movement of the switch member.

It should be understood that my invention is not limited to specific details of construction and arrangement thereof herein illustrated, and that changes and modifications may occur to one skilled in the art without departing from the spirit of my invention. What I claim as new and desire to secure by Letters Patent of the United States is:

1. Operating mechanism comprising actuating means and means to be actuated, a continuous flexible tension member interconnecting the aforesaid means for changing the direction of application of. the actuating force, saidflexible member being under tension when said actuating force is applied, means for guiding and restraining said flexible member for effecting the afore-' said change in direction of actuating force, said guiding and restraining means including a crank having a comparatively small efl'ective lever arm in the operative position, and tripping means causing release of said guiding means so that the resulting slack in said flexible member permits reverse movement of said means to be actuated.

2. Operating mechanism comprising actuating means and means to be actuated, a flexible tension member interconnecting the aforesaid means and adapted to be tensioned by said actuating means for changing the direction of application of the actuating force, means including a crank coacting at one end with said tension member for guiding and restraining the same so that said change in direction is of. the order of 90 degrees, and tripping means for releasing said crank so that the resulting slack in said tension member permits reverse movement of said means to be actuated.

3. Operating mechanism comprising an actuating solenoid having a reciprocally operable plunger, a member to be actuated reciprocally movable in a direction generally transverse to the direction of movement of said plunger, a flexible tension member interconnecting said plunger and said member, a pivoted element including a roller mounted at one end thereof for coacting with said tension member for guiding and restrainingthe same along a path of changing direction, actuation of said solenoid effecting a pull on said tension member to move said reciprocally operable member in one direction, and tripping means for releasing said pivoted member so that the resulting slack in said tension member permits reverse movement of said reciprocally operable member.

4. Operating mechanism comprising an actuating solenoid having a reciprocally operable plunger, a member reciprocally movable in a direction generally transverse to the direction of movement of said plunger, a chain linkage interconnecting said member and said plunger, a bell crank having a roller at one end for guiding and restraining said chain linkage in tension, the pivot of said bell crank being disposed within the angle through which said chain linkage is tensioned so that the reacting force on said bell crank tends to rotate the same from its restraining position, and latching means coacting with the other end 01' said bell crank for releasing the same so that said chain linkage is slackened and ineffective to hold said reciprocally operable member in its operated position.

, 5. Operating mechanism of the trip-free type for electric circuit breakers comprising a solenoid having a reciprocally operable plunger, a switch member reciprocally operable in a direction generally transverse to the direction of movement of said plunger, a chain linkage interconnecting said plunger and said switch member, a bell crank having a roller at one end for guiding and restraining said chain linkage along a path defining an angle of approximately 90 degrees, the tension applied by said plunger to said chain linkage in operating said switch member to the closed circuit position tending to rotate said bell crank to a non-restraining position, a resetting spring biasing said bell crank toward said position, a prop member normally restraining said plunger in its operated position, said bell crank being adapted to cause release of said prop in accordance with releasing movement of said bell crank and tripping means coacting with said bell crank for restraining the same and said chain so that the resulting slack in said chain linkage permits circuit opening movement of said switch memb r.

6. Operating mechanism '10: electric switches comprising an actuating solenoid having a reciprocally operable plunger, a switch member reciprocally movable in a direction approximately at right angles to the direction of movement of said plunger, a chain linkage interconnecting said plunger and switch member, a bell crank having a guide roller for said chain for restraining said chain along a path generally coincident with the angle between said directions of movement, the pivot of said bell crank being within said angle and onset with mspeet to the bisector of said angle so that tension applied to said chain by said plunger tends to rotate said bell crank from its restraining pwition, and latching means coacting with said bell crank for holding the same in said restraining position, actuation oi said latching means and the resulting slack in said chain linkage permitting reverse movement of said switch members CARL THUMIM. 

